docs: S3 compatible adapter docs and Cloudflare R2 setup example

AdminForth/1703/make-s3-adapter-support-url-pa

Author: yaroslav8765

adminforth/documentation/docs/tutorial/06-Adapters/04-storage-adapters.md

@@ -11,15 +11,61 @@ Used for storing files.
 ## Amazon S3 Storage Adapter
 
 ```bash
-pnpm i @adminforth/storage-adapter-amazon-s3
+pnpm add @adminforth/storage-adapter-amazon-s3
 ```
 
-Stores uploaded files in [Amazon S3](https://aws.amazon.com/s3/), providing scalable cloud storage. It can be forked and customized to work with S3-compatible services such as MinIO, Wasabi, or other third-party S3 providers.
+Stores uploaded files in [Amazon S3](https://aws.amazon.com/s3/), providing scalable cloud storage. 
+
+## S3 compatible adapter
+```bash
+pnpm add @adminforth/storage-adapter-s3-compatible
+```
+
+Provides S3 compatible interface for object storage services such as MinIO, Wasabi, Cloudflare R2 or other third-party S3 providers.
+
+
+### Cloudflare R2 setup example
+
+This adapter requires key/value adapter. For example, we will be using levelDb adapter.
+>‼️Since levelDb is used for storing keys of objects, that should/shouldn't be deleted, so this is important to use docker volume on deployed application, so you will not loose this data after re-deploy 
+```bash
+pnpm add @adminforth/key-value-adapter-leveldb
+```
+
+1) Go to the [Cloudflare dashboard](https://dash.cloudflare.com/) and create new bucket. Get bucket URL.
+2) Get R2 Access key id and Secret access key
+3) Add in the .env file: 
+```
+R2_ACCESS_KEY_ID=your_access_key_id
+R2_SECRET_ACCESS_KEY=your_secret_access_key
+R2_ENDPOINT_URL=your_bucket_url
+R2_BUCKET_NAME=your_bucket_name
+R2_BUCKET_REGION=auto
+```
+4) Setup adapter:
+```ts
+  import LevelDBKeyValueAdapter from '@adminforth/key-value-adapter-leveldb';
+
+  new AdminForthAdapterS3CompatibleStorage({
+    accessKeyId: process.env.R2_ACCESS_KEY_ID as string,
+    secretAccessKey: process.env.R2_SECRET_ACCESS_KEY as string,
+    endpoint: process.env.R2_ENDPOINT_URL as string,
+    bucket: process.env.R2_BUCKET_NAME as string,
+    region: process.env.R2_BUCKET_REGION as string,
+    s3ACL: "private",
+    cleanupKeyValueAdapter: new LevelDBKeyValueAdapter({
+      dbPath: './cloudflare_r2_storage_keys',
+    });,
+    forcePathStyle: true,
+    cleanupCheckInterval: '30m',
+    cleanupGracePeriod: '5d'
+  }),
+```
 
 ## Local Storage Adapter
 
 ```bash
-pnpm i @adminforth/storage-adapter-local
+pnpm add @adminforth/storage-adapter-local
 ```
 
 Stores files locally on the server filesystem. It is suitable for development or small self-hosted setups, but cloud storage is generally a better production option for reliability and scalability.